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CHAPTER 10
Dermal Hazards
Learning Objectives
• Identify key anatomy and physiology of the skin.
• Understand how toxic agents are absorbed into the body
through the skin.
• Describe several of the most significant adverse health
effects of skin exposure to hazardous agents.
• Explain some of the latest methods of dermal exposure
assessment.
• Develop controls necessary to minimize skin exposure to
hazardous agents.
Anatomy of the Skin
Source: Franklin and Morgan 2005
Anatomy of the Skin (cont.)
Source: snapgalleria/iStock
Main Mechanisms of Diffusion
1) Travel on the intercellular lipid pathway
Source: Centers for Disease Control and Prevention
Main Mechanisms of Diffusion (cont.)
2) Trans-cellular permeation
Source: Centers for Disease Control and Prevention
Main Mechanisms of Diffusion
3) Through appendages of the skin
Source: Centers for Disease Control and Prevention
Main Mechanisms of Diffusion (cont.)
Source: Scheuplein 1971
Chemical Exposure
• Touching contaminated surfaces
• Being immersed in containers with liquids or semisolids
• Sedimentation, impact, electrostatic attractions, or
chemical splashes depositing aerosols on the skin
Chemical Factors of Absorption
• Molecular weight
• Hydrophylic
• Lipophylic
• Volatility/vapor pressure
Skin Injury and Illness
• 33,000 cases per year
• >$1 billion in costs
Contact Dermatitis
• Known as eczema
• An inflammation of the superficial regions of the skin that
appears in large localized areas
• Characterized by inflammation and erythema (reddening)
or the formation of scales
• Symptoms of dermatitis include itching, swelling, pain,
burning, rashes, redness, blisters, and dry or flaky skin.
Contact Dermatitis (cont.)
Source: Centers for Disease Control and Prevention
Irritant Contact Dermatitis
• A nonimmunologic reaction that results from direct
damage following exposure to a hazardous agent and
manifests as inflammation of the skin
• 80% of all cases of occupational contact dermatitis
Phototoxic Contact Dermatitis
• Develops only after exposure to UV light, such as sunlight
Allergic Contact Dermatitis
• An inflammation of the skin caused by an immunologic
reaction triggered by dermal contact with a skin allergen
or sensitizer
• Plants (gardening), antibiotics (pharmaceutical industry),
dyes (paint and cosmetics industry), metals, chromates
(cement industry), adhesives, fragrances, rubbers, resins,
pesticides, fertilizers, and cutting oils used in machining
Exposure Pathways
• Immersion
• Splashes
• Deposition
• Contact with contaminated surfaces
Urticaria
• A transient skin condition that often appears as a wheal
(swelling) and raised patches accompanied by intense
itching
• Caused by skin irritants or allergens and is different from
dermatitis because it typically occurs rapidly following
exposure and often goes away soon after exposure
ceases
• Caused by detergents, pesticides, rubbers, minerals, and
animal toxins such as from caterpillars, jellyfish and
certain plants
Acne
• An inflammatory disease of the sebaceous glands and
hair follicles in the skin, leads to pimples and pustules
(white-centered bumps) on the surface of the skin
• Often develops in jobs where workers are exposed to
materials like oil, grease, pitch and tar
Systemic Diseases That Result
from Skin Exposure
• Diseases that result in other parts of the body after a
dermal exposure
• Can cause respiratory and neurological effects
• May lead to bladder cancer, scrotal cancer, and heart or
kidney disease
Physical Damage to Skin
• Can represent a significant hazard in many industries and
should not be forgotten.
• Cuts, abrasions, burns, rashes, cysts, frostbite
Skin Cancer
• Most common form of cancer
• Treatment in the U.S. costs $8.1 billion per year
• 10,000 people die from melanoma each year
• Polycyclic aromatic hydrogen compounds, creosote and
mineral oils have been associated with benign skin
cancer.
• Ultraviolet and ionizing radiations have been closely
associated with malignant melanoma
Common Dermal Exposures
Dermal Exposure and Toxicity
Controlling Skin Exposure
• Elimination and substitution
• Engineering controls
• splash guards, glove boxes, isolation booths
• Administrative or work practice controls
• training, good hygiene, access control, procedures
• PPE
• footwear, aprons, face shields, overalls, and gloves
Skin Care Products
• Certain creams can be used to provide a barrier to
hazardous chemicals.
• Moisturizers can be used to treat damaged skin.
• Cleaners can be used to remove skin contamination.
• Sun block can be used to reduce effective dose to UV
radiation.